Technical Field
The present disclosure relates to a drill used for an implant surgery for recovering a lost tooth of a patient, and more particularly, to a drill for an implant surgery which allows a mucous membrane in the maxillary sinus to be fast and safely lifted without being damaged during a surgery for the maxillary sinus.
Description of the Related Art
A conventional implant surgery method for the maxillary sinus has been classified into two kinds of approaches, i.e., a lateral approach and a crestal approach.
In the conventional crestal approach, an osteotome surgery using an osteotome surgery kit has been widely used. In the osteotome surgery, drilling processes are executed from an initial drilling stage to a final drilling stage according to an implant surgery plan, and then a malleting process is conducted by using the osteotome surgery kit. At this time, the cortical bone is lifted and at the same time its surrounding cancellous bone is compressed, so that a denture may be implanted. However, during this surgery, the malleting process induces impacts and noise, so that a patient may feel a pain such as a headache, and thus an operator has no choice but to execute a surgical procedure under the psychologically unstable state due to any possible pain of the patient.
The cranial bone of a human body has empty spaces such as maxillary sinuses, frontal sinuses and sphenoidal sinuses, which serve to reduce the weight of the cranial bone and cause a sound to be resonated, and there are mucous membranes between such empty spaces and the cranial bone. The existence of such mucous membranes disturbs the implant surgery when an operator tries to approach the maxillary sinus and implant a denture.
Problems at the surgery may occur when the maxillary sinus is drilled for the purpose of implanting a denture in the empty space of the maxillary sinus. In other words, the mucous membrane in the maxillary sinus may be easily torn when a blade of a drill for use in an implant surgery comes in contact with the mucous membrane during the rotation of the drill for the perforation of the maxillary sinus or an operator applies an excessive force instantly and inadvertently. The torn mucous membrane may cause problems such as infection, so that an operator should be always cautious in order not to tear the mucous membrane.
While performing a drilling work by rotating the drill, the operator mostly determines the perforation of the maxillary sinus depending on his/her feeling at fingertips. The operator generally checks a perforation depth by measuring the thickness of the maxillary sinus with X-ray or computerized tomography (CT) before performing the surgery. However, since the bone in the maxillary sinus has various shapes such as planar shape, concave shape and septum shape so that the mucous membrane may be perforated due to various inner shapes of the maxillary sinuses, the operator always feels psychologically burdened during the surgery.
In order to lessen the burden of the operator as described above, various methods have been proposed. For example, a drill tip may be made blunt in order that the mucous membrane cannot be torn even though the rotating drill tip comes into contact with the mucous membrane. Alternatively, a drill may be designed to be rotated at a lower speed or at a manually controlled speed in which a cutting ability of the drill is reduced. In another case, a diamond grit of small particles may be attached to a tool so as to gnaw the bone.
However, since the drilling work is performed at a lower speed to prevent the mucous membrane from being torn in the conventional drills, there is a disadvantage in that the drilling work may take a long time.
In addition, there are other problems in that cut bone chips cannot be easily cut and discharged, some cut portions of the bone during the drilling operation may be abruptly and locally heated due to a frictional heat between the drill and the cut portions, and the mucous membrane may be perforated while the operator inadvertently gives an excessive force thereto.